Unidentified Flash from Space

Supernovae usually flare for 3-7 weeks, so scientists don't think SCP 06F6 is one, as it "continued to brighten over the next 100 days, peaked, and then finally faded to oblivion over another 100 days."

According to the report at Wired:

The scientists can tell very little about the source of the flash — not even how far away it is, or how intrinsically bright. That means it could have come from some event in our own galaxy, or from some distant region of the universe. There is no visible star or galaxy at the site of flash to offer hints of what caused it.

Since the astronomers first announced the mystery sighting, many experts have offered guesses about what type of phenomenon could be behind it. Suggestions include a new type of supernova (such as the collapse and explosion of a unique star), a collision between a white dwarf star and a black hole, or even an exotic star made out of hypothetical “mirror matter.”

...Some are even joking that it could have been caused by an alien civilization that had just turned on its own version of the Large Hadron Collider and blown itself up.

I find it ironic that there are so many mysteries like this one, yet orthodox science assures us that we are completely safe.